Traditionally, surgical training and skill development has been performed in the operating room on living patients. However, there are increasing medical, legal and ethical concerns about the use of patients as a learning platform by surgical trainees.
An alternative is the use of surgical skill laboratories where organs and tissues from animals and human cadavers are used. There is an obvious limitation to both of these approaches, where animal models might not be as accurate as human anatomically and human cadavers are costly and often in limited supply. While human cadavers provide the advantages of presenting the correct anatomy, they disadvantageously do not possess the proper feel of living human tissues, since body is embalmed by submerging in chemicals that change the mechanical properties of the tissues. Additionally, cadavers are expensive and have disposal issues as they have to be disposed by incineration due their biohazard classification. The potential for infectious disease transmission is another concern.
An alternative but still costly solution is to provide live animals as surgical teaching resources. Indeed, live animals such as pigs may be used in beating heart surgical training sessions. However, live animals do not possess the right physiology, when compared to human tissues and organs. Furthermore, live animals can necessitate approval of the ethics board and animal rights groups, and also may require expensive animal facilities with well trained veterinary staff.
Another option is to provide explanted animal tissues and organs, such as porcine hearts, which are relatively inexpensive. Unfortunately, such biological samples require special handling, can present problems with transgenic contamination, and require disposal as a ‘biohazard’.
Recently, synthetic polymer simulator devices have been employed as testing devices. Unfortunately, state-of-the-art anatomic replicates suffer from numerous disadvantages that have hampered their widespread adoption as teaching tools. Such devices are typically based on silicone rubber, polyurethane, natural rubber, PVC, or foam, and therefore do not replicate properties or the “feel” of the real organs and do not provide an optimal experience to surgical skills training. While these models may look quite realistic, they fail in producing realistic response in the surgical steps of handling, cutting and suturing, their general ‘feel’ or mechanical behavior is often very different from that of the natural tissues. Accordingly, such materials do not provide the necessary material properties to be used as effective surgical teaching tools.
The need for improved synthetic surgical training aids was recently highlighted by Hwang et al. (G. Hwang, C. W. Oh, S. Q. Park, S. H. Sheen, J. S. Bang, and H. S. Kang, “Comparison of Different Microanastomosis Training Models: Model Accuracy and Practicality”), who compared the performance of synthetic anastomosis tubes with that of animal models. The synthetic anastomosis tubes used were shown to significantly underperform animal models with regard to both practicality and accuracy.
What is therefore needed is a new class of devices and methods for teaching surgical techniques, in which the mechanical and visco-elastic response of real tissues is reproduced with improved accuracy.